You could use a List or a Map to implement the relationship; however, a Map offers the advantage that it can provide fast lookup given, say, the book catalog number as the key.

可以用List或Map实现这个关系；但是Map提供的优势是它能提供快速的查询，也就是说用图书目录编号作为键。

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Designate the valve size and the complete catalog number, including prefix and suffix letters, when applicable, to identify regular cataloged items as described on the following pages.

在订购时，请指定阀门通径和完整的产品规格型号，包括前缀和后缀，有关规格型号的含义请参阅下列网页中描述的常规项目及其说明。

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A microbial strain cited and identified by its ATCC catalog number shall be used directly or, if subcultured, shall be used not more than five passages removed from the original strain.

通过ATCC的目录号引用和鉴定的微生物菌种应该直接使用，如果再次培养，不能从原菌群中移去超过五个菌落数。

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By crowdsourcing the task of tagging the photos to micro-volunteers, the museum can catalog a greater number of photos without the expense of paying staff.

FORBES: Connect

So today it announced that to augment those slim sales, Kozmo will begin duplicating its online offerings in a print catalog and publicize a toll-free number, in order to attract customers who are less Internet-savvy.

FORBES: Another Swing And Miss For Kozmo.com

One startup that has a number of venture capitalists excited is Redbaby, which started out as a catalog company and has now gone online.

FORBES: Hanging out with VCs at Tsinghua